I would presume that since God is all-powerful, all-knowing, and so on, God could Himself use ways to communicate with us that only each individual him or herself understands, and indeed this actually does happen. Of course there are Messengers, or Prophets, of God that figure out ways to explain divinity to certain people in certain ways, but nobody, and I mean nobody, understands God completely in the same ways as anybody else. The way everybody understands God, from a group of atheists, to the most fervent fundamentalist Christian religious denominations, is going to be unique to each individual, no matter what label or description of God they use to describe themselves. This is because God is reality, and that perception of reality is different from each brain and from each unique individual experience each person has. Likewise, I call my idea of God being reality panentheism, but even those who agree with me, and also believe in panentheism, might disagree on core concepts of divinity and other theological beliefs.
God doesn't just have the ability to communicate with anyone, in my panentheist beliefs, God already does this by natural means of evolution and the core five senses we have: hearing, sight, taste, touch and smell. And with our ability to think and perceive things with language, each and every person has the ability to interpret this reality as they sense it themselves. This is why God is so contested from so many people: different experiences from different people with different thoughts and different backgrounds are obviously going to have different results when it comes to understanding God. Understanding God means you understand reality, something no person been able to fully been illustrated to this point yet. There have been movies which God is character, explaining Himself to someone using the vernacular they understand, typically setting things to happen a certain way to correct them, like with An Interview With God or with the popular show God Friended Me.
The truth is, however, reality itself already does all the things that character does on all of those shows, we don't need some all-knowing, all-powerful person to guide us in any of it, because we already know innately what we're here to do and why we're doing it. Wikipedia has a long article dedicated to the reason why people exist, but it's obvious to me that people exist to have the time to do things they want to experience while they're alive, and as long as they aren't harming anyone else, or themselves in fact, there should be no barrier between the reality that is and the reality they wish to see one day. And that to me is how I understand God.
